An automatic aerotriangulation system is described. Its design and development have been made to possibly meet every requirement from photogrammetric practice. The system consists of five components, i.e. block preparation, fully automatic tie point determination, semi-automatic control point measurement, interface to diverse block adjustment programs and block post-processing. A relational data base takes care of communications among individual components. The fully automatic tie point determination plays a key role in the whole system. Its realization follows the principle of image connection and thus exhausts the technical potential to reach the highest level of automation. The system is now in daily operation in practice. Results achieved using the system are promising. It was proven that automatic aerotriangulation provides higher reliability of results and much more economy to the photogrammetric practice than ever before.